The calamondin (Citrofortunella microcarpa) is a hybrid citrus fruit resulting from the crossing of a mandarin orange with a kumquat. It is a small, round-shaped fruit with thin, smooth skin ranging from orange to dark red. The aroma of the fruit is distinctive and unique. Calamondin is an excellent source of Vitamin C, D-Limonene, and essential oils, providing benefits to the immune system, as well as anti-inflammatory, anti-cancer, anti-diabetic, anti-angiogenic, and anti-cancer properties, and it exhibits various therapeutic effects. It also contains a good amount of dietary fiber from pectin. Its distinctive flavor and high juice content make calamondin juice a popular ingredient in many international cuisines. The juice also contains bioactive compounds, such as phenolics and flavonoids, which are a potential source of antioxidant properties. All parts of the calamondin fruit, including the juice, pulp, seeds, and peel, can be used in various applications, from food products like juices, powders, and candies to non-food uses in herbal medicine and cosmetics, showcasing their versatility and unique properties. This review will examine various bioactive components of calamondin and their related medicinal effects, and provide guidelines for their utilization, processing, and value addition on a commercial scale.

Safe transfusion depends on rapid, accurate ABO typing, yet reference methods require centrifuges and instrumentation unavailable at the point of need. Here, a paper-based ABO-RhD typing device built on a covalent, optically silent surface chemistry is reported. Aminosilane (APTES) and epoxysilane (GPTMS) functionalisation of Whatman cellulose was compared by water contact angle, energy-dispersive X-ray spectroscopy (SEM-EDS) and infrared spectroscopy (FT-IR) across two paper grades, three silane concentrations (5, 10 and 20% v/v) and three reaction times (1–6 h). APTES produced a strongly hydrophobic layer that impeded aqueous wicking, and its glutaraldehyde activation generated a red-brick chromophore incompatible with a red-channel readout. GPTMS coupled antibodies in a single mild step, without a crosslinker or visible chromophore, while preserving wicking. GPTMS (10% v/v, 3 h, Whatman No. 4) with a six-cycle 100 µL saline wash was selected; antibodies were immobilised in a four-zone layout (anti-A, anti-B, anti-D and control) within a 3D-printed two-compartment housing that traps agglutinated cells while free cells wash through. On 80 EDTA clinical blood samples (20 each of groups A, B, AB and O) the device classified every sample correctly (accuracy 100%; 95% confidence interval 95.4–100%), with visual and instrumented reads in full agreement. All samples were RhD-positive, so the anti-D channel is validated here for the positive call.